Saajid Badat, who has become Britain’s first terrorist supergrass, was once
described by a family friend as a “walking angel”.

A quiet and respectful pupil at the prestigious Crypt Grammar School for Boys in Gloucester, he attained 10 GCSEs and four A-Levels before being offered a place at Imperial College London to study optometry.

But the devout Muslim, who memorised the Koran by the age of 12, had also spent time as a teenager in Sarajevo during the Balkan conflicts of the 1990s.

He travelled to Afghanistan for jihad training, telling his parents in a letter: “I have a sincere desire to sell my soul to Allah in return for paradise.”

While at the military camps he met Richard Reid and just three months after Al-Qaeda flew passenger jets into the Twin Towers, the British pair were recruited by terrorist chiefs to detonate explosives on planes crossing the Atlantic.

Reid tried to light the fuse on his shoe bomb on a flight from Paris to Miami on December 22, 2001, but was overpowered by passengers and crew and later jailed in America.

Badat wore a shoe filled with high explosive on flights to Amsterdam, Istanbul and Manchester and was due to fly to America from Amsterdam at the same time as his co-conspirator.

But he became the shoe bomber who got cold feet, emailing his handlers to say he had been having “big problems” and adding: “You’ll have to tell Van Danne that he could be on his own.”

Badat dismantled his device but kept the plastic explosive in one suitcase at the Gloucester home of his parents and the detonator in another, together with the US dollars he had been given before his suicide mission.

He enrolled at the Wal-Huda College for Islamic Education and Guidance in Blackburn in February 2002, training to be a priest.

In November 2003, however, police raided his family home and the college and on the way to the station he blurted officers: “I was asked to do a shoe bombing like Richard Reid.”

He went on: “I know I’ve done wrong but I want to help the police now.”

Six years after he admitted conspiracy to destroy an aircraft at the Old Bailey, earning a 13 year sentence, the full extent of his co-operation is only just becoming known.